Crank-case ventilator



y 1960 E. R. OLSEN CRANK-CASE VENTILATOR 2 Sheets-Sheet 1 Filed Oct. 27, 1958 1 l l I .llllllll INVENTOR:

ERNEST May 24, 1960 E. R. OLSEN CRANK-CASE VENTILATOR Filed Oct. 27, 1958 2 Sheets-Sheet 2 INVENTOR:

R. OLSEN ERNEST 2,937,629 Ice Patented May CRANK-CASE VENTILATOR Ernest R. Olsen, 6956 Grand Haven Road, Spring Lake, Mich.

This invention relates to internal combustion engines, and particularly to a system for the ventilation of crankcases. It is now generally recognized that much of the corrosion and consequent damage to the working surfaces of an engine is due to the presence of acids resulting from the condensation of combustion gases. The removal of these gases before they can become intermixed with the lubricating oil and condensed into corrosive liquids is an eifective means for prolonging the life of the engine parts. These general principles are well-known. This invention provides a device which can be placed in engagement with the usual oil-fill tube to induce the evacuation of the crankcase without involving separate power-driven equipment. The energy provided by the slip stream of the cooling fan is utilized as the source of the pressure differential to evacuate the crank-case, and a very economical construction of formed sheet-metal is provided by this invention for the necessary structural components. The invention will be analyzed in further detail through a discussion of the particular embodiments illustrated in the accompanying drawings. In the drawings:

Figure 1 presents a view in elevation, partially in section, taken from the down-stream end of the unit, and looking forward.

Figure 2 presents a side elevation of the device shown in Figure 1.

Figure 3 illustrates a closure cap in side elevation.

Figure 4 presents an elevation of the transverse conduit used in the assembly.

Figure 5 presents a view in end elevation of the closure cap shown in Figure 3.

Figure 6 illustrates a top view of the unit shown in Figure 4, Figures 4 and 6 being in projection.

Figure 7 presents a view in elevation of the perforate cylinder used as a filter.

Figure 8 presents an end view of the filter shown in Figure 7.

Figure 9 presents a view in side elevation of the air duct passage of the assembly.

Referring to the drawings, the illustrated ventilating device includes a cap 10 which is placed in firm engagement wtih oil-fill tube 11 of a conventional internalcombustion engine. It is preferable to form the cap with a discontinuity at the point indicated at 12 to limit the degree of engagement of the cap with the vent tube so that an upper extension 13 is provided beyond the end of the oil-fill tube. The top of the cap 10 is closed by the plate 14.

The opposite sides of the cap are pierced to form holes to receive the transverse conduit 15. Referring to Figure 1, the left end of the conduit receives a perforate filtering unit 16 which is best shown in Figure 7. This component can be of any convenient construction; and in the illustrated form, consists of a cylindrical perforate strip of material with a perforate end closure. This filter unit is slipped into the left end of the transverse conduit and is positioned by the annular ridge 17,

the length of the filter unit being in excess of the length of the opening 18 in conduit 15. The ridge 19 is formed in the conduit 15 to limit the penetration of the conduit within the cap 10, and to establish a positive position of the conduit with respect to the cap. Afterthe filter unit 16 has been inserted, the closure cap 20 is forced in place to lock the filter unit in position and close off the otherwise open left endof the conduit 15.

The opposite end of the conduit 15 from the closure cap 20 is cut off at 21 on a plane disposed at an angle to the axis of the conduit 15. A tab 22 is left on the end of the conduit for engagement with the arcuate opening 23 in the air duct tube 24, and the tab 22 may be crimped after assembly to lock the components in the relative position shown in Figure 1. The opening caused by the slanted cut at 21 on the end of the conduit is mounted to face down stream within the air duct 24, and the flow of air past the conduit induces a suction within the conduit 15. This flow of air is induced by the air scoop 25, which is preferably disposed a short distance behind the cooling fan of the engine. The air scoop 25 can conveniently be formed as a substantially conical surface, and the normal relationship of the components of most internal combustion engines suggests that the air duct 24 be eccentric to the center of the opening of the air scoop, with the air scoop center being somewhat below that of the axis of the air duct 24. The position of the opening of the air scoop is indicated in dotted lines at 26 in Figure 1.

If the engagement of the cap 10 with the fill tube 11 is not tight enough to prevent rotation of the assembly about the axis of the fill tube, a conventional key or locking system (not shown) can be used. This is a matter of choice on the part of the designer, and is not essential to the practice of the invention. It is suggested that the down stream end of the air duct 24 be connected to a flexible hose for conducting the vapors of the engine (mixed with the draft from the cooling fan) to some point outside the engine compartment to avoid the possibility of these vapors finding their way into the interior of the vehicle. The suction caused by the venturi action at the end 21 of the transverse conduit results in a reduction of pressure within the crank-case, and it is conventional to provide these engines with a venti- V lating tube which extends underneath the engine, and is commonly referred to as a road draft. With this arrangement, it is possible to reduce the pressure in the crank-case so as to increase the tendency of the gases to remain in the volatile form (rather than condense into corrosive liquids), and also to urge a ventilating flow of air through the crank-case to cause a flushing action.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is my intent to claim the entire invention disclosed herein, except as I am limited by prior art.

I claim:

1. A ventilator for the crank-case of internal combustion engines having an oil-fill pipe, said ventilator comprising a cap receivable over the-end of said oil-fill pipe, said cap having an extension beyond the end of said pipe; a transverse conduit intersecting the opposite sides of said extension and having an aperture within said cap, said transverse conduit emerging from both sides of said cap, said transverse conduit having a projection from said cap terminating in a normally rearward-facing opening defined by a plane intersecting said conduit at an angle to the axis thereof; filter means insertable in the opposite end of said transverse conduit from said projection and covering said aperture to prevent the entrance of o 3 foreign material into said oil-fill pipe; closure means for said opposite end; and air duct means including an airscoop normally facing toward the front of an engine, and also. including an air passage surrounding said opening and extending rearward therefrom i 2. A ventilator for the crank-case of internal combus tion engines having an oil-fill pipe, said ventilator comprising a cap receivable over the end of said oil-fill pipe, said cap having an extension beyond the end of said pipe; a transverse conduit intersecting said extension and having an aperture within said cap, said transverse conduit having a projection from said cap terminating in a normally rearward-facing opening defined by a plane inter secting said conduit at an angle to the axis thereof; and air duct means including an airscoop normally facing toward the front of an engine, and also including an air passage surrounding said opening and extending rearward therefrom.

3. A ventilator for the crank-case of internal combustion engines having an oil-fill pipe, said ventilator comprising a cap receivable over the end of said oil-fill pipe, said cap having an extension beyond the end of said pipe; a transverse conduit intersecting said extension and having an aperture within said cap, said transverse conduit having a projection from said cap terminating in a 25 normally rearward-facing opening; and air duct means including an airscoop normally facing toward the front a 4 of an engine, and also including an air passage surrounding said opening and extending rearward therefrom.

4. A ventilator for the crank-case of internal combustion engines having an oil-fill pipe, said ventilator comprising a cap receivable over the end of said oil-fill pipe, said cap having an extension beyond the end of said pipe; a transverse conduit intersecting said extension and having an aperture within said cap, said transverse conduit having a projection from said cap provided with an opening; and air duct means including an airscoop normally facing toward the front of an engine, and also including an air passage surrounding said opening.

5. A ventilator for the crank-case of internal combustion engines having a pipe leading to said crank-case, said ventilator comprising a cap receivable over the end of said pipe, said cap having an extension beyond the end of said pipe; a transverse conduit intersecting said extension and having an aperture within said cap; and air duct means including an airscoop normally facing toward the front of an engine, and also including an air passage surrounding an opening in said conduit.

References Cited in the file of this patent UNITED STATES PATENTS 

